Vegetation liquors are obtainable, among other ways, either directly from plants for the purpose of extracting useful components or as a waste stream in the processing of plant material which is often the cause of environmental pollution leading to the degradation of waterways and sources of water. In this invention, the vegetation liquors derived from oil-bearing fruit may be obtained from or using one of the following:                a) oil-bearing fruit of any herbaceous or arboraceous plant or from a combination of such fruit,        b) fruit of the oil palm plant,        c) waste streams from oil mills that process oil-bearing fruit,        d) palm oil mill effluent or concentrated palm oil mill effluent,        e) steriliser condensate from a palm oil mill,        f) waste from any oil clarification stage at a palm oil mill,        g) waste from any centrifuge stage at a palm oil mill, or        h) waste from any oil trap at a palm oil mill.        
The above list is not intended to exhaust the possible sources of vegetation liquors derived from oil-bearing fruit and any other such sources not named explicitly, for example, olive flume wastewater, are meant to be included as input material for the invention. It will be clear that the input material is not restricted to pure fruit but also includes any ancillary vegetative matter collaterally processed with the fruit.
In the case of oil palm fruit processing, the extraction of palm oil generates a waste stream of vegetation liquor at more than twice the tonnage of the crude palm oil production. Currently there are several treatments and uses for vegetation liquors like palm oil mill effluent. Among them are either applying said effluent, with or without treatment, onto the crop growing area, or reduction of chemical and biological oxygen demand before release of treated effluent into the environment, or generation of feed for livestock, or generation of substrates for the growth of micro-organisms (“A novel treatment process for palm oil mill effluent”, Ma Ah Ngan et al, PORIM Technology No. 19, October 1996). The use of membrane filtration in the treatment of such effluents, whether in research or in practice, has hitherto been focussed upon one or more of the above objectives rather than those aims which are the subject of this invention (“Palm oil mill effluent treatment by ultrafiltration: An economic analysis”, Mohd. Tusirin Nor et al, Second Asean Workshop on membrane technology, 1982). However, existing treatments have not really provided a solution to the effluent problem, and proposed solutions do not seem to have been widely adopted perhaps because of adverse economics.
Furthermore, it has hitherto been accepted palm oil mill practice that the recovery of any remaining oil from effluent is not carried out despite the presence in said effluent of nominally one to two percent oil content, often more in reality. Similarly, palm oil mill effluent has hitherto been ignored as a potential source of water-soluble biologically active compounds including, but not limited to, flavonoids, phenolic acids and hydroxy acids. Neither has the oil palm fruit been used as a source for such compounds nor as a source of a drink or tonic based upon its aqueous part.